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• We numerically show that an ultra-thin Weyl semimetal film can achieve an excellent performance of a high polarization extinction ratio (more than 40 dB) and a low insertion loss (less than 0.07 dB). • Monolayer polarizer shows that the optimum insertion loss is not achieved in the band with the highest PER. An isotropic substrate has little effect on the TM mode, while effectively adjusts the position of TE mode transmission peak. Thus, the proposed sandwich structure can further reduce insertion loss (from 0.06 dB to 0.03 dB) and obtain wider acceptances range of angle (from 49. 5 ∘ to 71 ∘). • Due to the high reflectivity of the two interfaces inside the WSM layer, the incident light is reflected several times in the single-layer structure, forming a structure similar to the Fabry-Perot cavity, which seriously affects the polarizer's performance. To overcome the challenges above, the proposed a gradient Fermi level structure eliminates the interference peak, thus resulting a wider bandwidth (approximately 60 % improvement). This method can be generalized to larger thickness cases. • With the increasing demand for on-chip integrated devices, our work can be helpful for the integration of a range of potential optical applications in optical communication and omnidirectional polarization detectors. Recently, Weyl semimetals have been extensively studied due to their unique optical responses, especially in the mid-infrared region. However, the possibility of developing optical polarizers based on Weyl semimetals remains unexplored. In this paper, under the Voigt geometry, we numerically show that an ultra-thin Weyl semimetal film with thickness L = 100 nm can achieve an impressive polarization extinction ratio (more than 40 dB) with a wide acceptance angle. Further, the proposed sandwich structure can effectively adjust the position of the TE mode transmission peak alone, thus obtaining lower insertion loss (from 0.06 dB to 0.03 dB) and wider acceptance range of angle (from 49. 5 ∘ to 71 ∘). The proposed gradient Fermi level structure eliminates the Fabry-Perot cavity resonance, thus resulting a wider bandwidth (approximately 60 % improvement). Our proposed ultra-thin and wide-angle polarizer may have potential applications in optical communication and omnidirectional polarization detectors. [ABSTRACT FROM AUTHOR]

Dingkun Pill (DKP) is a traditional Chinese medicine that has been shown to have beneficial effects on reproductive function. However, the specific mechanism underlying its effect on POI is not well understood. To investigate the effect of different doses of Dingkun Pill on ovarian function in cyclophosphamide (CTX)-induced premature ovarian insufficiency (POI) mice and to explore its molecular mechanism through PTEN/PI3K/AKT/FOXO3a signaling pathway. This study will provide valuable insights into the potential clinical application of Dingkun Pill for the treatment of POI. Fifty female ICR mice were randomly divided into normal control (NC) group, model control (MC) group, and Dingkun Pill low, medium, high dose (DKP-L, M, H) groups. Mice were injected with CTX to construct the POI model. Mice in the DKP-L, M, and H groups were given 0.9 g/kg, 1.8 g/kg, and 3.6 g/kg of Dingkun Pill suspension for 21 days, respectively. Mice in the NC and MC groups were given the same amount of normal saline by gavage. Changes in body weight, estrous cycle and gonadal index were observed in each group of mice. Serum levels of FSH, LH, E2 and AMH were detected by ELISA. Hematoxylin-eosin (HE) staining observed the changes of ovarian pathological morphology and follicle counts at all levels. qRT-PCR was used to measure the levels of the PTEN and FOXO3a genes in ovarian tissue. The expression of PTEN/PI3K/AKT/FOXO3a signaling pathway related proteins were detected by Western-blot and immunohistochemistry (IHC). In POI mice, Dingkun Pill increased body weight, promoted the recovery of estrous cycle, increased ovarian index, and improved pathological morphology of the ovaries. The FSH level decreased in the medium dose group (P < 0.05), the LH level reduced significantly in the medium and high dose groups (P < 0.01), and the E2 level in the high dose group increased (P < 0.05). There was no significant difference in AMH levels across all dose groups. The number of growing follicles improved at all levels in the low and medium dose groups, but declined significantly in the high dose group. However, the number of corpus luteum increased significantly in the high dose group (P < 0.001), and the atretic follicles in the three dose groups decreased. Results from qRT-PCR, Western-blot and IHC showed that the moderate dose of Dingkun Pill suppressed the levels of the p-PI3K and p-AKT proteins by upregulating the expression of PTEN in the ovarian tissues of POI mice, thereby inhibiting the expression of the key protein p-FOXO3a. However, the inhibitory effect of the higher dose may be less than that of the lower and intermediate dose groups. The Dingkun Pill modulated hormonal levels, promoted follicle growth and induced ovulation in mice with CTX-induced POI, with better results in the low and moderate dose groups. Its mechanism may be related to the regulation of the PTEN/PI3K/AKT/FOXO3a signaling pathway. [Display omitted] • Effect of Dingkun Pill on the estrous cycle of POI mice. • Effect of Dingkun Pill on serum sex hormone levels in POI mice. • Effect of Dingkun Pill on ovarian morphology and follicle count in POI mice. • Effect of Dingkun Pill on PTEN and FOXO3a gene expression levels in ovary tissue of POI mice. • Effect of Dingkun Pill on the expression of PTEN/PI3K/AKT/FOXO3a pathway using western-blot and immunohistochemical method. [ABSTRACT FROM AUTHOR]

In order to improve the network security and get the real-time situation of network security, the access control method of network security authentication information based on fuzzy reasoning algorithm is proposed. Firstly, a scheme of multi-data source analysis and situational perception assessment is proposed based on the factors of network physical security and service security. At the same time, on the basis of multi-source data fusion, fuzzy reasoning algorithm is used to mine and identify the network attack relevance, so as to achieve the perception control of network security situation. Then based on security situation mining control, role classification is introduced to realize network access control. Finally, the access control flow is designed by combining the physical structure, logical structure and use case diagram of access control. The multi-level security concept and role inheritance are used to control access, and the administrator role is used to restrict some users' operation of transferring access rights. The experimental results show that the method has good security situation perception effect, excellent performance and reliability of network access control. [ABSTRACT FROM AUTHOR]

Photoperiod and temperature are two main factors in the growth of macroalgae, and changes in photoperiod and diurnal temperature difference exist in natural condition. In order to study the effects of photoperiod and diurnal temperature difference on the growth of green algae Ulva prolifera , we cultured this species under three light/dark cycles (light: dark = 10:14, 12:12 and 16:08) with constant (22 °C for light and dark period, noted as 22-22 °C) and diurnal temperature difference (22 °C and 16 °C for light and dark period, respectively, noted as 22-16 °C) conditions. The results showed that: 1) Compared with 10:14 light/dark cycle, the growth of U. prolifera under 12:12 light/dark cycle was significantly enhanced by 39% and 16% for 22-22 °C and 22-16 °C treatments, respectively, while the increase proportion decreased when the daylength increase from 12 h to 16 h. 2) The enhancement in growth induced by diurnal temperature difference was observed under 10:14 light/dark cycle, but not for 12:12 and 16:08 light/dark cycle treatments. 3) The Chl a content and photosynthetic rate increased under short light period and 22-22 °C conditions, while under 22-16 °C conditions, higher photosynthetic rate was observed under 12:12 light/dark cycle and no significant difference in Chl a content was observed. 4) Under 22-22 °C conditions, compared with 10:14 (L:D) treatment, the expression levels of proteins in light-harvesting complexes, PSII and carbon fixation were down regulated, while the photorespiration and pentose phosphate pathway (PPP) were up regulated by 16:08 light dark cycle. Then we speculate that the higher photosynthetic rate may be one compensation mechanism in short photoperiod, and under long light period condition the up regulations of photorespiration and PPP can be in charge of the decrease in enhancement growth induced by longer daylength. • The growth of U. prolifera was enhanced by diurnal temperature difference under short daylength, but not for long daylength. • With the increase of daylength, the growth of U. prolifera increased, but the proportion of this enhancement decreased. • The photosynthetic rate increased under short light period. • The photorespiration and pentose phosphate pathway (PPP) were up regulated by longer daylength. [ABSTRACT FROM AUTHOR]

The structural instability of metal oxides retards realizing high-performance and long lifespan supercapacitors. We prepare an electrochemical active heterostructure of NiCo layered double hydroxide (LDH) confined by carboxyl carbon nanotube (CNTCOOH). Through the electrostatic interactions between carboxyl groups (COO−) of CNTCOOH and metal cations of LDH under a simple hydrothermal treatment, the CNTCOOH confined NiCoLDH (CNTCOOH- c -NiCoLDH) can be easily fabricated. The CNTCOOH- c -NiCoLDH demonstrates the specific morphology of rope-fastened plates and shows ultrahigh cycled stability. In addition, the hydrophilic carboxyl groups on CNTCOOH also regulates the interfacial electronic coupling and electrolyte soaking, resulting in high rate capability. The charge-storage capacitance of CNTCOOH- c -NiCoLDH heterostructures reaches 2120.8 F/g at 1 A/g. The devices of CNTCOOH- c -NiCoLDH//AC show both high energy density (171.0 Wh/kg) and high power density (950.0 W/kg), and have ultrahigh capacity retention rate of 93.64 % after 50,000 charge and discharge cycles at a high current density of 5 A/g. This work supports an effective confinement idea and a facile method that can be applied on a large scale for the design and fabrication of super high stable metal oxide-based supercapacitors. [Display omitted] • Through the strengthened interactions between carboxyl of CNTCOOH and metal cations of LDH, CNTCOOH-c-NiCoLDH is prepared. • The specific capacitance of CNTCOOH-c-NiCoLDH flowers reaches 2120.8 F/g at a current density of 1 A/g. • CNTCOOH-c-NiCoLDH//AC shows high capacity retention rate of 93.64 % after 50000 cycles at 5 A/g. [ABSTRACT FROM AUTHOR]

Poly(3-hydroxybutyrate) (PHB), as a kind of bioplastics for sustainable development, can be synthesized by various microorganisms, however, the high cost of its microbial fermentation is a challenge for its large-scale application. In this study, piperazine degrading strain, Paracoccus sp. TOH, was developed as an excellent chassis for open PHB fermentation with piperazine as controlling element. Whole-genome analysis showed that TOH possesses multi-substrate metabolic pathways to synthesize PHB. Next, TOH could achieve a maximum PHB concentration of 2.42 g L−1, representing a yield of 0.36 g-PHB g−1-glycerol when C/N ratio was set as 60:1 with 10 g L−1 glycerol as substrate. Furthermore, TOH could even synthesize 0.39 g-PHB g−1-glycerol under non-sterile conditions when piperazine was fed with a suitable rate of 1 mg L−1 h−1. 16S rRNA gene sequencing analysis showed that microbial contamination could be effectively inhibited through the regulation of piperazine under non-sterile conditions and TOH dominated the microbial community with a relative abundance of 72.3% at the end of the operational period. This study offers an inspired open PHB fermentation system with piperazine as the control switch, which will realize the goal of efficient industrial biotechnology as well as industrial wastewater treatment. • Poly(3-hydroxybutyrate) synthesis capability was identified in Paracoccus sp. TOH. • TOH could utilize various carbon sources for PHB biosynthesis. • A PHB yield of 0.36 g-PHB g−1-glycerol with PHB titer of 2.42 g L−1 were observed. • Piperazine acts as controlling element for the open PHB fermentation system. • Microbial contamination was effectively inhibited under non-sterile conditions. [ABSTRACT FROM AUTHOR]

• Fertilizer distribution depends on the speed at the outlet of the mixing cavity. • Uneven dispersion of fertilizer granules due to directly falling from blade gaps. • Fertilizer mixed by double-blade has lower outlet speed than that of single-blade. • Mixing effect of multi-fertilizers by air blowing & double-blade stirring is best. In proportional variable-rate fertilization, improving the uniformity of multi-fertilizer mixing helps to improve the overall utilization efficiency of fertilizers. In this paper, a multi-fertilizer mixing by air blowing and blade stirring was presented. Using fertilizer granules mixing uniformity as an indicator, the method optimized the structures and working parameters of single-blade group stirring, double-blade group stirring and air blowing & double-blade stirring. EDEM and Fluent software were used for the simulation and the results were verified by experiments. The simulation results showed that the appropriate speed range of single-blade group stirring was 600 ∼ 900 r⋅min−1 and the highest mixing uniformity was achieved with the blade mounting angle α of 20°. The best structure of double-blade group stirring was achieved with an upper blade mounting angle β of 20°, a lower blade mounting angle θ of −20° and a spacing h of 89 mm. For the air blowing & double-blade stirring method, the best results were achieved when the input air velocity v a was 8.4 m⋅s−1 and the blade speed of agitator n b was 740 r⋅min−1. The mixing uniformity of nitrogen (N), phosphate (P) and potash (K) fertilizer granules reached 98.41%, 98.12% and 98.31%, respectively. The bench test results showed that the mixing uniformity by air blowing & double-blade stirring was better than that by double-blade group, and the mixing uniformity by double-blade group was better than that by single-bladed group, which were consistent with the simulation results. Meanwhile the differences between experimental values and simulation values were within 2%, which showed that the simulation models were reliable. Results from this study can be used as reference for the design of mixing devices of variable-rate fertilization. [ABSTRACT FROM AUTHOR]

• Hindquarter of cow's back in depth image was located. • 3D structure feature map of point clouds was constructed. • Two-step EfficientNet model was built for BCS. • 91.21% images were scored with the error less than 0.25. Body condition score (BCS) is an important indicator to evaluate the nutritional and health status of perinatal dairy cows. The insufficient accuracy of the automatic body condition score is the core bottleneck restricting the popularization and application of this technology. To further improve the accuracy of automatic scoring of cow body condition, a 3D structure feature map based on convex hull distance of point clouds was constructed and used as the input of a two-level model based on EfficientNet network, which realized the improvement of recognition accuracy within the error of 0.25 in the automatic scoring of cow body condition. First, the depth image of the cow's back was preprocessed to obtain the point cloud from the hook bone to the needle bone region containing the main body condition information. Second, the point cloud was voxelized and convex hulled, and the distance between each peripheral voxel and the nearest convex hull surface was calculated and projected to the X-Y plane to obtain the structural feature map. Then, a two-level classification model based on the EfficientNet network was constructed, and the whale optimization algorithm (WOA) was used to optimize the network scaling coefficient in the model. Finally, 5119 depth images of 77 cows were used to train and test the model, and the dataset ratio was 1:1. The results showed that when the BCS value was in the range of 2.25 to 3.75 and the two-class classification limit was 2.75, the proportions of images with recognition errors less than 0.25 and 0.50 were 91.21% and 97.60%, respectively, and the average recognition speed was 3.446 frames/s. The recognition effect was better than that of the MobileNet-V2, XceptionNet and LeNet-5 network models. This method could realize the noncontact assessment of individual body conditions of dairy cows in large-scale farms and had the characteristics of high accuracy, strong applicability and low cost. [ABSTRACT FROM AUTHOR]

In this paper, the safe sealing temperature range of tempered glass was determined to be no more than 300 °C by experiments. On this basis, the feasibility of silver oxide system low melting solder (SOSLMS) used in tempered vacuum glazing (TVG) sealing was explored by sealing strength experiment, scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and other test methods. The results of sealing strength experiment showed that the bonding strength of the sealing layer was inversely proportional to the sealing temperature. The bonding strength of the sealing layer in the range of 260 °C–290 °C met the standard requirements (not less than 0.6 MPa) except for the failure of the sample sealing at 300 °C. The observation results of SEM showed that when the sealing temperature was 260 °C and 270 °C, the solder layer had uniform fusion and dense structure, and the sealing layer was tightly bonded. With the increase of sealing temperature, the solder layer began to produce large holes, and there was obvious open gap between solder layer and glass substrate after stretching. The analysis results of EDS showed that the Ag and V elements all diffused into the glass at each sealing temperature, the difference of diffusion concentration and distribution was not significant. The analysis results of XRD showed that when the sealing temperature was in the range of 260 °C–270 °C, there was no crystallization phenomenon in the SOSLMS. When the sealing temperature was in the range of 280 °C–300 °C, Ag 2 VO 2 PO 4 crystals began to precipitate, and with the increase of temperature, the higher the crystallinity was, the greater the crystal content was. In conclusion, in the range of 260 °C–270 °C, the SOSLMS showed good sealing performance, which was suitable for TVG sealing. • A kind of silver oxide system low melting solder was considered to be suitable for tempered vacuum glazing sealing. • The optimal sealing temperature range of silver oxide system low melting solder was 260 °C–270 °C. • The bonding strength of the sealing layer was inversely proportional to the sealing temperature. • The precipitation of Ag 2 VO 2 PO 4 crystals was considered to be the fundamental reason of the reduction of bonding strength. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultra-high S BET and porous structure enhance the performance of the biochar. • Surface-bound radicals and electron-transfer participate in BPA oxidation. • The system has a superior durability and strong resistance to real water matrixes. • DFT confirmed the pyrrolic N was beneficial for the decomposition of PDS. Nitrogen configurations doped in carbon matrix serve as the catalytically active sites for the metal-free activation of persulfates (peroxydisulfate PDS, and peroxymonosulfate PMS). Herein, a series of pyrrolic N-rich biochars (BDKx, where x represents the pyrolysis temperature) were facilely prepared by using waste bean dregs as the feedstocks. The resulted BDK900 possessed ultra-high specific surface area (S BET , > 3000 m2 g−1). Accordingly, it exhibited superior catalytic activity in PDS activation, as evidenced by the efficient removal of bisphenol A (BPA, 1358.4 mg g−1) with 0.05 g L−1 BDK900 and 5 mM PDS. Surface-bound radicals and electron-transfer mechanism were discovered to contribute to the BPA oxidation, during which BDK900 played vital roles in PDS activation, BPA accumulation, and regulating electron shuttle from BPA to PDS. Overall, this study sheds new light on the rational design of N-rich biochar and develops a low-cost technology toward remediation of BPA-contaminated wastewater. [ABSTRACT FROM AUTHOR]